Temozolomide will be evaluated for safety, efficacy, maximum tolerated dose and pharmacokinetics in patients with Anaplastic Astrocytoma experiencing first relapse. Temozolomide will be administered orally 1/day x 5 days every 28 days. Pts will fast 4 hrs before & 2 hrs after each dose. Pharmacokinetics will be drawn on Day 1 Cycle 1. All patients will be drawn at baseline (before dosing) and 4 times post-dosing.